The present invention relates to a card connector including contacts divided into two kinds of contacts for detecting a card for one particular purpose and others for further purposes.
In recent years, memory cards have become popular and a wide variety of memory cards have been used which are different in size and thickness and the like. Card connectors have also been provided for use with electronic appliances for such memory cards. There is a requirement for the card connectors which can accommodate such a variety of memory cards. For example, Japanese Patent Application Opened No. 2002-8755 (particularly in FIG. 1) discloses a card connector for use with a plurality (for instance; two) of cards.
In further progress, there has also proposed a card connector 100 for use with three kinds of cards C1 to C3 as shown in FIGS. 6 to 8. In the card connector 100, card insertion openings 110 and 120 for the cards C1 and C2 are arranged side by side on the front side of the card connector, while a card insertion opening 130 for the card C3 is arranged in overlapping relationship to whole the card insertion opening 120 for the card C2 and part of the card insertion opening 110 for the card C1. In other words, in the proposed card connector 100, whereas its versatility may be enhanced, the card insertion openings 110 to 130 for the cards C1 to C3 are arranged in high density in a limited space on the front side of the card connector in order to avoid an increase in its geometry for achieving miniaturization as much as possible.
In the proposed card connector, moreover, a great number of contacts 140 are arranged in the internal card receiving space compatible with the respective card insertion openings 110 to 130 for exchanging stored data between the cards C1 to C3 and components and for controlling various components. Among these contacts 140, for example, the contacts for the cards C1 and C2 have their connecting portions or soldering legs hanging down from the front face of the card connector so that the front end of the card connector lacks a space for the contacts for the card C3. As shown in FIG. 7, therefore, the contacts for the card C3 extend unavoidably to the rear end of the card connector 100 so that their connecting portions or soldering legs 141 are caused to hang down from the rear end of the connector. These soldering legs 141 of the contacts for the cards C1 to C3 are connected by soldering to circuit boards or the like on the side of electronic appliances.
Owing to such a space limited construction, the card receiving space for the card C3 becomes in overlapping relationship to the card receiving spaces for the cards C1 and C2. As shown in FIG. 8, therefore, the contacts 150 for detecting whether or not the card C3 exists are arranged in a contact receiving portion 160 provided in a little clearance between the card receiving spaces 111 and 131 for the cards C1 and C3.
The contacts 150 are each made of an elongated metal plate piece whose shape is as shown in FIG. 9. The contacts 150 each have a detecting portion (switching portion) 151 made of a bent piece on the side of the card insertion opening 130 for detecting an existence of the card C3. Usually, the contacts 150 having the detecting portion 151 are inserted into the card insertion opening 130 and press-fitted and installed in the contact receiving portion 160, thereafter the rear ends of the contacts 150 extending from the rear end of the card connector 100 are bent to form soldering legs 152.
Such contacts of the proposed card connector suffer following disadvantages from their construction.    (1) First, in placing the contacts 150, slightly swelling protrusions 153 provided on both sides, in width direction of each contact 150 are press-fitted in recesses (not shown) formed in part of groove (on both sides thereof) in the contact receiving portions 160. These protrusions 153 and the recesses are usually at the locations nearer to the front ends of the contacts 150 (or to the card insertion opening 130) so that the soldering legs 152 of the contacts 150 on their opposite ends will be remote from their fitted protrusions 153 and hence the soldering legs 152 would be poorly or unstably supported which would in turn lead to defective or failed soldering of the legs in a soldering process by reflow soldering.
If protrusion 153 and the recesses are arranged at locations nearer to the soldering legs 152 of the contacts 150, the detecting portions 151 formed by the bent pieces would be likely to operate unstably or would cause failed contact with the card C3. It may be envisioned that the number of protrusions 153 and the recesses is increased to solve this problem. In this case, however, whereas the entire holding force for the contacts may be increased, greater force for press-fitting of the contacts would be required which would make difficult the press-fitting operation itself.
(2) In terms of the insertion of the contacts 150 from the side of the card insertion opening 130 for placing them in position, it is required for the contacts 150 to be formed as an elongated linear metal plate piece so that the freedom of design of the card connector itself would be limited.
(3) As described above, the soldering legs 152 of the contacts 150 have to be bent in later process step after the contacts 150 have been installed in the card connector, which would be problematical.